LOL buying cat fish never. If I want cat I just go to the lake, or my freezer. I have never caught a blue cat that big but flat heads yes several times. To catch flat heads ya use a jug line or limb line with a big ole gold fish as bait, when the rivers on the rise. For blues and channels I use shad sides that have been buried for a year, a trick my grand dad taught me. For trot lines I use crawdads. There is a lake not too far from my house under an hour away. Divers have gone down along the dam, and say they will never go back as there are cats in there bigger then they are. Can't say for sure it's true but that's what I hear. The dam is made of old RR box cars, so not imposable.
As to smoking cat I have tried it and don't care for it, I like them dipped in an egg wash, rolled in cornmeal and flour mix, and fried up.